1. Field
Example embodiments relate to athermal optical modulators and methods of manufacturing the same, and more particularly, to optical modulators that have a relatively small change in emitted wavelength with respect to temperature change and methods of manufacturing the same.
2. Description of the Related Art
An opto-photonic device uses an optical device for transmitting signals and uses electricity for inputting and outputting the signals. An optical modulator used in an opto-photonic device is manufactured by using mainly a semiconductor substrate, and a device that transmits optical signals may be formed of Si that is formed in a process compatible with a complementary metal-oxide-semiconductor (CMOS) process.
Optical modulators based on a silicon substrate include a mach-zehnder type modulator and a ring resonator type modulator. The ring resonator type modulator has a smaller size when compared with the mach-zehnder type modulator, is operated at a higher speed and has lower power consumption.
However, the optical modulator that includes Si has a problem of changing refractive index as temperature increases. Accordingly, due to the relatively high thermo-optic coefficient of Si, a propagation wavelength is changed, and as a result, a desired optical signal may not be transmitted. For example, an optical modulator formed of a silicon substrate may have a wavelength variation with respect to temperature of 0.11 nm/K.